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Recently, as it can increase the capacity of wireless networks greatly through spatial diversity by taking advantage of antennas on other nodes, cooperative communication (CC) has been obtaining more and more attention. However, as the selfish nature, the wireless node may be unwilling to serve as relay node if they can't get the corresponding reward. In this paper, we constructs a real double-auction scenario between source nodes and relay nodes instead of idealized truthful market which may obtain relatively lower system performance. We consider the system performance involving (1) successful source-relay pairs, (2) system capacity and (3) social welfare (SW). We transform the double auction-based optimal relay assignment problem into Maximum Matching (MM) and Maximum Weighted Matching (MWM) problem respectively and solve them using corresponding algorithms. Extensive experiments show that this mechanism can achieve higher system efficiency than truthful auction. [ABSTRACT FROM PUBLISHER]

Since a long time wireless networks have been offering two types of services: variable bit-rate such as mail and constant bit-rate such as voice. Recently they also offer service for streaming calls such as mobile television. The objective of the present paper is to study the problem of allocating (and sharing) the resources for this new type of calls and to compare the performance of different allocation strategies. The allocation strategy implemented in real networks is an iterative time-sharing strategy. We build an explicit formulation of this strategy which permits not only a faster implementation, but also an analytical evaluation of its performance. Moreover we describe an optimal allocation strategy consisting of assigning the resources in priority to the least consuming ones. A cornerstone to evaluate and compare the different allocation strategies is the so-called outage probability defined for each location as the probability that a user in this location doesn't get his required bit-rate. We compare the efficiency of different numerical methods to calculate it; and show that the inverse Laplace method is rapid and efficient. We also calculate the increase of the outage probability of the time-sharing strategy compared to the optimal one. Finally, we validate a method permitting to calculate analytically the average of the outage probabilities over the different locations. [ABSTRACT FROM PUBLISHER]

The processes of changing the channel associated with the current connection while a call is in progress is under consideration. The estimation of dropped calls is received with simulation of handover at one dimensional traffic system with two level priority schemes. Blocking calls at base station channels and handover queue overflow is considered as rare event and simulated with Importance Sampling — one of rare event simulation approaches. The simulation algorithm is worked out and simulation program is realized on PhP. Simulation results are shown. [ABSTRACT FROM PUBLISHER]

The processes, connected with wireless cellular network modelling and simulation is under consideration. On the base of provided comparative analysis of standards IEEE 802.11, 802.16 and 802.21 is chosen the type of network. The influence of network structure — nodes, connections between them, number of handover channels and handover queues, on the network throughput is studied. Simulation of basic networks nodes and their connection at 2G and 3G network is provided and experimental results for Quality of Service (QoS) probabilistic parameters are shown. [ABSTRACT FROM PUBLISHER]